Trip mechanism for punch presses



Fild Feb. 20,

INVENTOR Patented Jan. 15, 1935 ean 311 A MF R U G ?gmissfifi"? Frank S. Aliano, Biitioklvfli 7 Application Eebruary 20', 1934, Serial No; 712,157 IZ-Claims. (c1. 192-?82.)

The inventiourelatesto trip mechanisms for, punch presses and; more; particularly to a, trip mechanismof these-called non-repeat type, or one in which, with each actuation of the trip mechanism, the operation of the press; is

limited to a singlereciprocation of the ram,

In the operation of power driven, manually fed punch presses, it is a common practica with some operators, to hold the trip pedal depressem and to rely upon their skill in hand, feeding blanks to the dies, to secure substantially continuous operation of the press. times happens that ancperator fails to release the trip pedal in time to make the clutch setting member inoperative before the completion of,

one revolution of the crank shaft, thus inad vertently causing. an immediate and unexpected repetition of the operation of the press, or releasesthe pedal so quickly as to fail to actuate i the clutch setting member for, a sufficie'nt interval to ensure a proper setting of the ciut-ch. Therabove practices and occurrences have been the source of frequent injury to press operators while hand feeding blanks to the dies.

With a continuously operating press as duringblanking operations when an automatic feeder is used, safety devices are not required Prior to my invention, it has been proposed to provide a, trip mechanism for punch presses embodying therein mechanisms intended to, ac-

tuate the cam for setting the clutchof a punch press, by the manual depression of a trip pedal, andto restore said cam by an automatic release of the trip mechanism following the initial en- I gagement of the clutch members. Various safety devices have also been devised by, which the feeding of blanks to the dies upon the press is so controlled as to prevent the hands of an operator being positioned between the dies while the ram is in motion or to cause, anautomatic stoppage of the ram in the event of the hand beingso positioned.

While safety devices preventing the feeding of blanks to the dies, in the manner above referred to, have been extensively and satisfactorily used, safety devices. of the type to which, the invention relates, to wit: those which make the mechanism for setting the clutch members inoperative through the automatic action of the trip mechanism, have lacked that certainty and reliability in their operation necessary to their successful use in the prevention of accidents.

Another difficulty with trip mechanisms of the type above referred to, is that they are not adapted to the adjustment of the upper part It also some 7 t e c e t i les; ii s amas fen ivin e ha 9 esti es g r ns leritn aieqi iielts the ee 9 acks to themes ih Q1- hthe conditions in mind, I have. p ovided, a trial meshei isni "op rati e, u on e uncht r ss' sla es; qiiua iselm m r n tuated by, mea nso J an, ordinary foot pedal, h h; mechanism ama ium-t e that with he en fis on Qt; messe we ut h, e n smbetvw l esermfiien a to use a sune; a s. utch durinathet ot iibn ii efl s h which the pedal is depri ssed, and will eposition in me ch n m brina mat s a' i cii nr nl s a e lt fr he qieue he ra k shaft o lowirig the; setting oi, the clutch This avoids possibility of z a failure to propfir y engage e l ch mem ers, ue o a em tu e ea of the clutch pedal on a, premature aut9matic actuation of the trip m mechanism; of the. i

t ion, th operation or s though there were. a direct connection between the pedal and the clutch actuating member as in the ordinary press, while ensuring an automatic functioning.

The automatic relase mechanism, forming a part ofthe trip mechanism, is so constructed as ,to reduce to a minimum possibility of such'a breakage or Ydisarrangem ent of parts as to inter-,- fere with a con tinue d reliable operation of the device. Furthermore, the construction is such that the trip mechanism may be so set as to,

make the, aut mat c me ha sms no e t ve hu p rm ttin an perat r, by a n n pression oi theclutch pedal, to cause a continuous operation or the press which is desirable iii some blanking operations from metal strips during which the hands of the operator are not required to be brought between the dies,

nism "W hth ri In the trip mechanism of the invention of the invention, the various operative parts of the automatic release mechanism are so constructed and arranged as to not only actuate the clutch setting member in a manner to ensure a proper setting of the clutch mechanism, but to cause the rapid resetting of the automatic mechanism upon the release of the pedal, thus placing no limitation upon the speed at which the press may be operated.

A further advantage of the mechanism of the invention is that it may be adapted by a simple adjustment of parts to any position of the upper frame of the press, thus permitting the adaptation of the attachment to any press and its continued operation notwithstanding customary adjustments of the press in adapting it to different kinds of work.

The invention consists primarily in a trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of independently movable clutch and pedal slides, restoring springs acting on said slides respectively, links connecting said clutch slide with said clutch setting member, and said pedal slide with said pedal, means carried by one of said slides and engageable with the other, whereby movement of said pedal slide will impart movement to said clutch slide, means whereby said slides will be disconnected as a result of movement of said pedal slide to permit movement of said clutch slide independently of said pedal slide, a

, ,latch member acting upon said clutch slide, and

wheel.

a member rotatable with said shaft and engageable with said latch member to disengage said latch member from said clutch slide; and in such other novel features of construction and combi- ,,nation of parts as are hereinafter set forth and described, and more particularly pointed out in the claims hereto appended.

Referring to the drawing,

Fig. 1 is a side elevation of a punch press ,,having applied thereto a trip mechanism' embodying the invention;

Fig. 2 is a section on the line 22 of Fig. 1;

and I Fig. 3 is a perspective view of the housing forming the guides and enclosing parts of the trip mechanism.

Like numerals refer to like parts throughout the several views.

In Fig. 1 of the drawing, the invention is shown as applied to an old and well known form of punch press, the upper frame 10 of which is adjustable in arcuate bearings 11 upon the base 12 to permit the bolster 13 to be positioned at any desired angle to facilitate the hand feeding of blanks to the die mounted upon the bolster.

The ram 14 is of the usual construction. The

flywheel of thepress is not shown in the accompanying drawing, since this is immaterial to an understanding of the invention.

The ram 14 is mounted in vertical guides 15 and is actuated by a rotatable shaft 16 having a collar 17 which carries one of the clutch members 18 by means of which the shaft is connected to the flywheel or other source of power.

Acting upon the clutch member 18 is a clutch setting member 19 ordinarily a cam plate adapted by engagement with said clutch member to move it out of the path of movement of a cooperating clutch member carried by the fly- To transmit power from the flywheel to the shaft 16, the member 19 is moved'downwardly out of the path or" movement of the clutch member 18 permitting this clutch member to be forced outwardly to a position where it will be engaged by its co-operating clutch member upon the flywheel. The elevating of the member 19 positions it so that with the turning of the shaft 16, the clutch member 18 will be moved out of engagement with its co-operating clutch member upon the flywheel.

The press is provided with the usual trip pedal 20 acted upon by the usual spring 21 and acting upon the member 19 to control the application of power to the ram 14.

The general construction and arrangement of parts as heretofore described is old and well known in the punch press art, and requires no further detailed description.

Secured to, and movable with, the upper frame 10 is a housing 22 having spaced guides 23 and 24 extending from top to bottom thereof. Mounted side by side within said housing and between said guides 23 and 24 and bearing upon each other are a clutch slide 25 and a pedal slide 26. These slides are of a length to project well beyond the top and bottom of the housing 22 which is provided with openings to permit such projection of the slides.

A suitable dished cover 27 is used to close the housing 22 and hold the slides against displacement from the-guides 23 and 24 and exclude dust and dirt from the working parts of the trip mechanism contained within the housing.

The clutch slide 25 is provided with upper and lower stop pins 28 and 29 which, by engagement with the housing Linit the reciprocatory movement of said slide. The pedal slide 26 is provided with similar upper and lower stop pins 30 and 31 for limiting the reciprocatory movement of that slide by engagement with the top and bottom of the housing 22 respectively.

Within the housing 22 are compression springs 32 and 33, acting respectively upon the bottom of the housing, and a spring seat 34 carried by and movable with each slide 25 and 26. The spring 32 acting upon the clutch slide 25, furnishes the energy to raise said slide in a manner to raise the clutch setting member 19 in a manner to disengage the clutch member 18 from its co-operating clutch member upon the flywheel of the press. The spring 33 serves merely to supplement the action of the pedal spring 21 in restoring the slide 26 to its uppermost position for the purpose of resetting the automatic trip mechanism preparatory to the next depression of the pedal 20.

The clutch slide 25 is connected by a link 35 with the member 19, and the pedal slide 26 is connected by a two part link with the shank of the pedal 20. The two parts 36 and 37 of the pedal link are connected by means of a clamp member 38, permitting variation in the length of this link to accommodate the trip mechanism to different settings of the upper frame 10.

The link section 36 is provided with a turned end 39, as shown in Fig. 2, having a loose fit in an opening through the slide 26, being secured in this position by means of a cotter pin, or in any other desired manner permitting the disconnection of the link from the slide when desired for a purpose to be hereinafter described. The slide 25 is provided with an opening passing therethrough adjacent the lower end of the link, it being possible to selectively connect the link section 36 with either slide 25 or 26.

One of the slides, as 26, supports a trigger which the cam 52 engages. ,The cam 52 is so mechanism by means of which this slide may be connected with the other slide as 2-5. to ensure simultaneous movement of these slides with the depression of the pedal 20. In the embodiment of the invention shown, this trigger mechanism comprises a lever 40-, pivoted at 4 .1 to the slide 26. This lever, adjacent one end thereof, is

provided with a pin 42 flattened on one side so as to afford a knife edge bearing with an abutment 43 formed upon the slide 25'.

The slide 26 is provided with an arcuate slot 44 to permit movement of the trigger in a manner to disengage the pin 42 from its co-operating abutment 43'.

The arm of the lever 40 opposite to that carrying the pin 42 is provided with a cam surface 45-adapted, by co-operation with a fixed stop" 46 secured to the wall of the housing 22, to rock said lever with downward movement of the slide 26 in a manner to disengage the pin 42 from the abutment 43 and thus permit movement of the slide 25 by the spring 32' independently of any movement of the slide 26. The lever 40 is acted upon by a spring 47 extending from a pin 48 upon the slide 26' to the one arm of the lever adjacent the cam surface 45, so as to normally engage the pin 42 with the abutment 43.

In the operation of the trip mechanism, the depression of the pedal 20 will, therefore, through'the sectional link 36 and 37, the auto matic release mechanism contained within the housing 22 and the link 35, actuate the clutch setting member 19 in a manner to cause the application of power to the shaft 16 through the clutch member 18, and toward the completion of the downward movement of the slides 25 and 26 will cause the actuation of the trigger mechanism, including the lever 40, in a manner to disengage the slide 26 from the slide 25 so that the spring 32 is free to move the slide 25 upwardly notwithstanding that the slide 26 is held by the pedal in its lowermost position.

With this actuation of the clutch slide 25, the member 19 is restored to its normal position preventing the engagement of the clutch member 18 with the co-operating flywheel clutch member; ince the pedal 20' maybe actuated at any time without regard to the relative position of the clutch member upon the flywheel and the clutch member 18, the mode of operation immediately above referred to might result in restoration of the member 19 to its position making the clutch mechanism inoperative before anypower has been applied to the shaft 16. Hence, it would be possible for the operator to actuate the pedal without any resultant movement of the ram 14 introducing into the actuation of the device an unreliability or undependability which would result in conditions so unsatisfactory as to preclude the use of the device.

To obviate the above difficulty, I provide a latch member 49, pivoted at 50 to the upper frame 10, one arm of this latch member being adapted to engage a latch tooth upon the clutch slide and the other arm of which is positioned by a spring 51 in the path of movement of a cam 52 carried by the collar 17 upon the shaft 16 when the latch member is engaged with the latch tooth upon the slide.

The latch member 49 is vertically adjustable in a fitting 53 by means of which it is pivotally mounted upon the frame 10 and carries at one end thereof an adjustable wear block 54 with position d in relation to the member 18 that it will not engage the latch member until after the clutch member 18 is in engagement with its co-operating clutch member upon the flywheel. Hence, the spring 32 cannot act to raise the slide 25 until after power has been applied to the shaft 16. The latch toothis shown at 55.

When it is desired to operate the punch press while the pedal is continuously depressed, it is essential that the construction be such as to permit the downward movement of the slide 25 in dependently of any movement of the slide 26', since with this mode of operation, the link section 36 is connected directly with the clutch slide 25 instead of being connected therewith through the slide 26 and the trigger mechanism.

To permit this movement of the slide 25, I pro-- videthis slide with a recessed portion 56 above the abutment 43 for a suifioient distance to permit movement of said slide in relation to the pin 42 to an extent to cause the actuation of the clutch setting member 19.

The operation of the herein described tripmeohanism is substantially as follows:

With the setting of parts as shown in Fig. 1 of the drawing, the operator, after feeding a blank to a die upon the bolster 13 by hand, depresses the pedal 20. A downward pull upon the sectional link 36 and 37 causes downward movement of the slide 26 within the housing 22 until the stop pins 30 engage the top of this hous ing. 'Duiing a major portion of this downward movement of the slide, the pin 42 of the trigger mechanism, by engagement with the abutment 43, draws the clutch slide25 downwardly with the pedal slide 26 against the tension of the spring 32, movement of the pedal 20 and the pedal slide 26 being against the tension of the springs 21 and 33.

During'the downward'movement of the slide 26, the engagement of the cam surface 45' with the fixed pin 46, causes rocking movement of the lever 40 against the tension of the spring 41'? until the pin 42 has pa'ssed from engagement with the abutment 43 into the slot 44. This cannot occur, however, until thelatch tooth 55 has passed below the lower end of the latch arm l 'so as to permit the engagement of said latch arm with said tooth by the/action of the spring 51. The parts will remain in this posi tion with upward movement of the slide 25 restrained by the latch lever 49, until the clutch from the latch tooth 55, thus permitting the spring 32 to raise the slide 25 and through the link 35, re-set the clutch setting member 19 so that the clutch member 18' will be disengaged from the clutch member upon the flywheel, upon the completion of one revolution of the shaft 16.

Were it not for the use of the latch memher so, the cam setting member 19 under some conditions, could be moved by the slide 25 with suflicient rapidity, after the disengagement of the trigger mechanism from said slide, to prevent a proper positioning of the clutch member 18 to ensure a transmission of power to the shaft 16 from the flywheel. Under other conditions, no such result would follow, but the mere possibility that the pedal might be depressed without resulting in the descent of the ram, introduces a lack of safety in the operation of the press, since the sequence of movements of the operator necessary in the operation of a press must be of almost clocklike precision, and anything which would interfere with this regularity in the movements of the operator makes the operation of a press extremely hazardous.

The practice of some operators, in endeavoring .to have a press operate continuously, is due to their desire to maintain an almost unconscious sequence of actions on their part in timing the feeding of the blank, the removal of a blank and the feeding of the next blank in synchronism with the movements of the ram without requiring the depression of the pedal for each cycle of the press.

The use of the latch lever 40 and the cam 52 avoids any possibility of the member 19 being prematurely restored to a position where it can prevent the setting of the clutch to to transmit power from the flywheel to the shaft 16, irrespective of the speed at which the pedal 20 may be actuated, since the latch arm 49 acting upon the clutch slide will hold the plate 19 in its lowermost position until said latch member is disengaged from its co-operating latch tooth by the rotation of said shaft 16.

The shaft 16 may turn at high speed, and when a pedal is depressed, the clutch member 18 and its co-operating clutch member upon the flywheel may be positioned but little less than 360 apart, or they may be spaced only a few degrees apart. Consequently, the timing of the initiation of the movement of the crank shaft is subject to wide variation within the time interval required for one rotation of the shaft 16.

The control of the movements of the clutch slide in the manner above described, corrects the above condition. It is desirable, however, to have as quick a resetting of the trigger mechanism as possible, and the action of the latch member does not place any restraint upon the return movement of the slide 26 which effects this resetting of the trigger mechanism. The recess 56 also permits a return of the slide 26 to its normal position, independently of any movement of the slide 25. The main purpose of this recess, however, is to permit the link section 36 to be connected with the slide 25 and to permit the actuation of this slide and of the clutch link 35 otherwise than through the slide 26.

The latch lever 49 may be adjusted in the block 53 to ensure accuracy in its relation to the latch tooth 55, and the wear block 54 may be adjusted along the length of this lever to properly position it in the path of movement of the cam 52.

The use of the link sections 36 and 37 and the connecting clamp member 38 permits variation in the length of this sectional link to permit arcuate movement of the automatic trip mechanism when changing the angle of the upper frame 10 of the press to bring the bolster plate 13 to any desired angle to facilitate the feeding of blanks to a die carried thereby.

While I use a spring 21 acting directly upon the pedal 20, and a spring 33 acting upon the slide 26, it is obvious that if desired, either of these springs may be omitted since the function of eachis merely to raise the pedal 20 and the slide 26 to their normal elevated positions.

The two slides 25 and 26 have a free sliding fit between the guides 23 and 24 and in relation to each other. They are made of heavy bar steel and are held between the guides by the closure 27. Consequently, there can be no loss of alinement or displacement of these slides, and they are readily accessible for installation purposes because of the removability of said cover. The said guides and the said slides may be read ily lubricated from the top of the housing.

The automatic mechanisms of the trip mechanism may be readily applied to any press irrespective of the form of the clutch mechanism used in that press.

Since the actuation of the flywheel clutch mechanism is dependent solely upon the extent of depression of the pedal, and since the functioning of the device in controlling the release of this clutch mechanism is not dependent upon the pedal action, it is obvious that the trip mechanism places no limitation upon the speed of operation of the press as compared with the normal operation without the automatic features of the trip mechanism.

The above mode of operation permits a rapid depression and quick release of the trip pedal, and necessitates the depression of said pedal to initiate each actuation of the press. The use of the trip mechanism prevents those practices of an operator which may result in an accident and does not necessitate the development of any acquired skill in operating a press equipped with the attachment. Its use increases the reliability in the operation of the press and avoids possibility of accident because of a lack of proper co-ordination of the movements of the operator with the mechanisms of the press.

It is not my intention to limit the invention to the precise details of construction shown in the accompanying drawing, it being apparent that such may be varied without departing from the spirit and scope of the invention.

Having described the invention, what I claim as new and desire to have protected by Letters Patent, is:-

1. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of independently movable clutch and pedal slides, restoring springs acting on said slides respectively, links connecting said clutch slide with said clutch setting member, and said pedal slide with said pedal, means carried by one of said slides and engageable with the other, whereby movement of said pedal slide will impart movement to said clutch slide, means whereby said slides will be disconnected as a result of movement of said pedal slide to permit movement of said clutch slide independently of said pedal slide, a latch member acting upon said clutch slide, and a member rotatable with said shaft and engageable with said latch member to disengage said latch member from said clutch slide.

2. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of a clutch slide, a pedal slide adjacent thereto, restoring springs acting upon said slides respectively, a trigger member upon one of said slides, an abutment upon the other slide, means normally engaging said trigger member with said abutment, guides for said slides, means upon said guides for disengaging said trigger member from said abutment with movement of the slide carrying same, links connecting said pedal slide with said pedal, and said clutch slide 31 9 8, roe

with'saidclutch setting member, a latch member "engageable with theclutch slide, and a member rotatable with said shaft and engageable with said latch -member todisengage said latch member from said clutch slide.

3. A trip mechanism for punch presses, em-- bodying therein the combination with a :rotatable shaft, a clutch setting member, and a foot pedal, of a clutch slide having an abutment thereon, a pedal slide adjacent thereto, restoring springs acting upon said slides respectively, a lever pivoted upon said "pedal slide, one arm 'of said lever carrying a ;pin engageable with the abutment on said clutch slide, and .the other arm of said lever having a cam surface thereon, a fixed pin in :the path of movementof the cam upon'said lever, a spring acting to enzgage said 'pin with said abutment and position said cam inoperative relation to said fixed pin, links connecting said pedal slide with saidpe'dal, and said clutch slide with said clutch setting member, ,a latch member engageable Withithe clutch slide, and a member rotatable with said shaft and engageable with latch member .to disengage said latch member from said clutch slide.

4. A trip mechanism for punch IDTB'SSGS, embodying therein the combination with a rotatable shaft, a clutch setting membenanda-foot pedal, of a housing having parallel guides formed therein, independently movable clutch i and pedal slides bearing upon said guides and each other, restoring springs acting on said slides respectively, links connecting said clutch slide with said clutch setting member, and said :pedal slide with said pedal, means carried 'by one of said slidesand engageable with the other,whereby movement of said pedal slide will impart movement to said clutch slide, means whereby said slides will be disconnected as :a result of movement 'of said pedal slide to permit movement of said clutch slide independently'of said pedal slide, a latch member acting upon said clutch slide, and a member rotataliile with said shaft and engageable with said latch member to disengage said latch member from said-clutch slide.

5. A trip mechanism for punch presses, embodying therein the combination with 'a rotatable shaft, a clutch setting member, and afoot pedal, of a housing having parallel guides formed therein, a clutch slide "having an abutment thereon, a pedal slide adjacent'thereto, said slides bearing upon said guides and each other, restoring springs acting upon said slides respectively, a lever pivoted upon said pedal slide, one'arm of said lever carrying apin engageable with the abutment onsaid clutch-slide, and the other arm'ofsaid lever havinga cam surface thereon,a fixed pin in the'path of movement of the cam upon said lever,'a spring-acting to engage said pin with said abutment and positionsaidcam inoperative relation to said fixed pin, links connecting said pedal slide with said pedal, and said clutch slide with said clutch setting member, a latch member engageable with the clutch slide, and a member rotatable with said shaft and engageable with said latch memher to disengage said latch member from said clutch slide.

6. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of independently movable clutch and pedal slides, restoring springs acting on said slides respectively, links connecting said clutch slide with said clutch setting member, and (said epedal slide with-said pedal, means carried by one of said slides .and *engageable with "the other, whereby movement of said pedal slide will -impart movement 2130 said clutch :slide, means whereby said slides will ibe disconnected 'as -:a result of'movement of said pedal rslide' to :permit movement of :saidclutch slide independe'ntly'of "saidf'pedal slide, a latch lever pivotally mounted intermediate said rotatable shaft and said slides, 'a latch tooth formed upon the end of said :clutch slide in engaging relation with one arm of said lever, aspringacting ;upon said :lever to engage rone :end thereof :with said tooth, and aaca'm rotatablewith said shaft and adapted to, engage the other-sarm of said lever, whereby upon the flowering of said clutch slide said ilatch lever will be engaged with its .co-operating -tcoth, and :upon the rotationiof said "shaft said latch lever "will be disengaged from said tooth to permit amovem'ent of {said clutch :slide by its spring.

7. A trip mechanismfor :punch presses, embodying therein=-the combination with a rotatable "shaft, a'clu'tc'h setting :member, and a foot Epedal, of 1 a housing having parallel guides :formed therein, a I clutch slide having an abutment thereon, a pedal slide-adjacent thereto, :said slides bearing upon said guides and each other, restoring springs'iacting upon said slides -respectively, azlever pivoted upon said pedal slide, one arm of-said levericarrying a pin engageable with the abutment on said clutch slide, and the other arm of said lever'having acam surface thereon, a fixed pin in athep'athof movement-of the oam upon said lever, a-spring acting to engage said .pin with said abutment and position said cam in operative relation to said fixed :pin, links connecting'said :pedal slide with said pedal, and said clutch slide with a said clutch setting -memher, a latch lever pivotally mounted intermediate said rotatable shaft :and said slides, a latch tooth formed upon the'end of said clutch'slide in engaging relation 'with "one arm of said lever, a spring .acting upon saidrlever .to engage one end thereof with said tooth,.and a'cam rotatable withsaidshaft and adapted to engage the other arm of said'lever, whereby upon the lowering of :said clutchrslide ."said latch "lever "will be engaged with its co operating tooth, and upon the rotation -'of said shaft said latch lever will be disengagedfrom saidtooth topermit a movemeritof "said cl1itch=slide by its spring.

8. A trip 'mechamsmior punch presses, tembodying Itherein the combination with a rotatable shaft, .a clutchzs'etting member, and aifoot pedal, of independently movable clutch and pedal slides, restoring springs acting on said slides respectively, a link connecting said clutch slide with said'clutchrsetting meniberga sectional link comie'cting said ipeda'l slide with said :pedal, means whereby the sections of said link may be adjusted to vary the length thereof, means carried by one of said slides and engageable with the other, whereby movement of said pedal slide will impart movement to said clutch slide, means whereby said slides will be disconnected as a result of movement of said pedal slide to permit movement of said clutch slide independently of said pedal slide, a latch member acting upon said clutch slide, and a member rotatable with said shaft and engageable with said latch member to disengage said latch member from said clutch slide.

9. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of a housing having parallel guides formed therein, a clutch slide having an abutment thereon, a pedal slide adjacent thereto, said slides bearing upon said guides and each other, restoring springs acting upon said slides respectively, a lever pivoted upon said pedal slide, one arm of said lever carrying a pin engageable with the abutment on said clutch slide, and the other arm of said lever having a cam surface thereon, a fixed pin in the path of movement of the cam upon said lever, a spring acting to engage said pin with said abutment and position said cam in operative relation to said fixed pin, a link connecting said clutch slide with said clutch setting member, a sectional link connecting said pedal slide with said pedal, means whereby the sections of said link may be adjusted to vary the length thereof, a latch lever pivotally mounted intermediate said rotatable shaft and said slides, a latch tooth formed upon the end of said clutch slide in engaging relation with one arm of said lever, a spring acting upon said lever to engage one end thereof with said tooth, and a cam rotatable with said shaft and adapted to engage the other arm of said lever, whereby upon the lowering of said clutch slide said latch lever will be engaged with its co-operating tooth, and upon the rotation of said shaft said latch lever will be disengaged from said tooth to permit a movement of said clutch slide by its spring.

10. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of independently movable clutch and pedal slides, each having means adjacent the bottom thereof whereby a link may be connected therewith, restoring springs acting on said slides respectively, a link connecting the top of said clutch slide with said clutch setting member, a link connected with said pedal and adapted to be selectively connected with either of said slides, means carried by one of said slides and engageable with the other, whereby when said last named link is connected with said pedal slide movement of said slide will impart movement to said clutch slide, said clutch slide being recessed adjacent said means to permit movement to be imparted to said clutch slide independently of said pedal slide when said last named link is connected therewith, means whereby said slides will be disconnected as a result of movement of said pedal slide to permit movement of said clutch slide independently of said pedal slide, a latch member acting upon said clutch slide, and a member rotatable with said shaft and engageable with said latch member to disengage said latch member from said clutch slide.

11. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of independently movable clutch and pedal slides, restoring springs acting on said slides respectively, links connecting said clutch slide with said clutch setting member, and said pedal slide with said pedal, means carried by one of said slides and engageable with the other, whereby movement of said pedal slide will impart movement to said clutch slides, means whereby said slides will be disconnected as a result of movement of said pedal slide to permit movement of said clutch slide independently of said pedal slide, a fitting pivotally mounted intermediate said rotatable shaft and said slides, a latch lever adjustably mounted in said fitting, a latch tooth formed upon the end of said clutch slide in engaging relation with one arm of said lever, a spring acting upon said lever to engage one end thereof with said tooth, a wear block adjustably mounted upon said lever arm adja cent said shaft, and a cam rotatable with said shaft and adapted to engage said wear block, whereby upon the lowering of said clutch slide said latch lever will be engaged with its cooperating tooth, and upon the rotation of said shaft said latch lever will be disengaged from said tooth to permit a movement of said clutch slide by its spring.

12. A trip mechanism for punch presses, embodying therein the combination with a rotatable shaft, a clutch setting member, and a foot pedal, of a housing having parallel guides formed therein, a clutch slide having an abutment thereon, a pedal slide adjacent thereto, said slides bearing upon said guides and each other, restoring springs acting upon said slides respectively, a lever pivoted upon said pedal slide, one arm of said lever carrying a pin engageable with the abutment on said clutch slide, and the other arm of said lever having a cam surface thereon, a fixed pin in the path of movement'of the cam upon said lever, a spring acting to engage said pin with said abutment and position said cam in operative relation to said fixed pin, links connecting said pedal slide with said pedal, and said clutch slide with said clutch setting member, a fitting pivotally mounted intermediate said rotatable shaft and said slides, a latch lever adjustably mounted in said fitting, a latch tooth formed upon the end of said clutch slide in engaging relation with one arm of said lever, a spring acting upon said lever to engage one end thereof with said tooth, a wear block adjustably mounted upon said lever arm adjacent said shaft, and a cam rotatable with said shaft and adapted to engage said wear block, whereby upon the lowering of said clutch slide said latch lever will be engaged with its co-operating tooth, and upon the rotation of said shaft said latch lever will be disengaged from said tooth to permit a movement of said clutch slide by its spring.

FRANK S. ALIANO. 

